Original Article: Clinical Investigation
Health-related quality of life and sexual function in women with stress urinary incontinence and overactive bladder
Won-Hee Park md, Department of Urology, Inha University Hospital, 7-206, 3-ga, Sinheung-dong, Jung-gu, Incheon 400-103, Korea. Email: firstname.lastname@example.org
Background: We evaluated the impact of stress urinary incontinence (SUI) and overactive bladder (OAB) on health-related quality of life (HRQOL) and sexual function.
Methods: A total of 245 women (SUI; n = 123 and OAB; n = 122) from 21 to 79 years old (mean 50.4) were included in the primary analyses. To obtain HRQOL and sexual function assessments, patients were asked to fill in the ‘Bristol Female Lower Urinary Tract Symptoms (BFLUTS)’ and the ‘Medical Outcomes Study Short Form (SF-36)’ questionnaires.
Results: Of the eight domains in the SF-36 questionnaire, only ‘general health’ was significantly different between the groups. Patients with SUI had a better general health than those with OAB (P = 0.016). When comparing the BFLUTS scores in the two groups, the score for ‘BFLUTS-filling symptoms’ was higher in the OAB group (P = 0.002) but that for ‘BFLUTS-incontinence symptoms’ was higher in the SUI group (P < 0.001). The score for ‘BFLUTS-sex’ was higher in the SUI group than in the OAB group but this was not statistically significant (P = 0.096). Of the 169 patients who had a sex life, the SUI group had experienced pain (P = 0.033) and leakage (P = 0.056) more frequently during intercourse than the OAB group.
Conclusion: Both SUI and OAB have a detrimental impact on patient HRQOL in Korean women. In addition, our findings suggest that women with SUI had more frequently experienced pain during intercourse and coital incontinence than those with OAB.
Urinary incontinence is defined by the International Continence Society as the complaint of any involuntary leakage of urine.1 It is a very common condition, affecting an estimated 13 million Americans. It is associated with significant morbidity and may have a considerable impact on a patient's health-related quality of life (HRQOL). Urinary incontinence may be classified as stress urinary incontinence (SUI), urge urinary incontinence (UUI), or mixed urinary incontinence.
Apart from impairing physical health, SUI may have a tremendous effect on psychological and social well-being. Women with SUI report an inferior HRQOL compared to continent women.2
Overactive bladder (OAB) is characterized by symptoms of urinary urgency and UUI, which are often associated with urinary frequency and nocturia, that appear without a local pathological or metabolic explanation.1 These symptoms and coping strategies together have a negative effect on patients' HRQOL. It has been suggested that patients with OAB often have greater HRQOL impairment than those suffering from SUI,2 but inconsistent results have also been reported.3 Thus, the results with respect to HRQOL may not be consistent in all aspect of HRQOL measurements or across different populations.
Sexual well-being is an important aspect of women's health, and dysfunction can lead to a decrease in HRQOL and affect the marital relationship. It has been reported in recent literature that women with urinary incontinence also have problems with sex.4–6 The presence of urinary leakage during intercourse can adversely affect the sexual experience,7 however it is unclear whether lower urinary tract symptoms (LUTS) increase the risk of sexual dysfunction in women or whether the two conditions are manifestations of the genitourinary changes seen with aging.8
To date, there are few studies comparing the results of HRQOL and sexual function in women with SUI and OAB. We examined the generic and disease-specific HRQOL using both generic (Medical Outcomes Study Short Form [SF-36]) and disease-specific (BFLUTS) HRQOL instruments and compared the results of these instruments in two groups. We also evaluated the impact of SUI and OAB on sexual function using a BFLUTS questionnaire.
Patients and methods
The study was conducted between February 2003 and January 2004. A total of 262 patients with LUTS were assessed. Patients were recruited from individual clinical practices at each hospital. The study inclusion criteria were being aged 18 years or older, and the ability to communicate, understand, and comply with the study requirements. The exclusion criteria were the use of medications for the control of bladder symptoms, neurogenic bladder dysfunction, the presence of urinary tract infection, malignancy, pregnancy, restricted mobility, an inability to read the questionnaire, cognitive impairment or psychiatric morbidity, and failure to give consent. SUI was defined as the involuntary leakage on effort, exertion, sneezing, or coughing. Urgency was defined as complaints of a sudden compelling desire to pass urine that were difficult to defer and UUI was defined as the complaint of involuntary leakage accompanied by or immediately preceded by urgency.1 Due to the small number, 17 patients with SUI combined with UUI were excluded from the study. In all, 245 patients (SUI; n = 123 and OAB; n = 122) were included in the primary analyses.
The data set of this study was derived from the database of a nation-wide multicenter study to evaluate the reliability and validity of the Korean Version of the BFLUTS instrument in the Korean population. The Institutional Review Board approved the multicenter study protocol and all of the patients provided informed consent. All patients were evaluated with history taking, a complete physical examination, urinalysis, urine culture and a 3-day frequency-volume (FV) chart. Uroflowmetry was performed in the sitting position. After uroflowmetry, postvoid residual urine volume was measured, then urodynamics were performed at room temperature 25°C To obtain HRQOL assessments, patients were asked to fill in the BFLUTS and the SF-36 questionnaires.
Each of the patients received two beakers (graduated in 10 mL increments), and was instructed as to how to complete a 3-day FV chart. They were also directed not to alter their usual fluid intake and voiding habits during the period of the study. The numbers and volumes of voids were estimated by taking a mean for 3 days. The times at which the patients arose in the morning and went to bed at night were noted on the FV charts. Nighttime was defined as the time from the patient's bedtime to the patient's rising in the morning for each of the registered nights.9 When assessing the FV chart, the first morning's void was included in the nocturnal urine volume. The first morning void was considered to be a normal diurnal voiding episode, however, and was not included in the total number of nightly voids. Several nocturia parameters including nocturnal polyuria index, nocturia index and nocturnal bladder capacity index were calculated.10,11
The SF-36 is a generic instrument to measure HRQOL12 and widely used to survey physical and emotional health. The validated Korean version of the SF-36 used in this study was provided by QualityMetric, Inc. (Lincoln, RI, USA) for the multicenter study. It consists of 36 questions grouped into eight dimensions: physical function (10 items), role limitations owing to physical health problems (4 items), bodily pain (2 items), general health perception (6 items), energy and vitality (4 items), social function (2 items), role limitations owing to emotional problems (3 items), and mental health (5 items). The results of the generic SF-36 questionnaire were then analyzed according to the method described by Ware et al.13 The number of questions directed to each health concept ranged from 2 to 10, and the number of response options per question ranged from two (no or yes) to six (none, very mild, mild, moderate, severe, or very severe). Each of the dimension scores was expressed as a value between 0 and 100, with greater scores representing better health.
Bristol Female Lower Urinary Tract Symptoms questionnaire
The BFLUTS questionnaire was designed to assess a wide range of symptoms and the impact on sexual function and HRQOL.14 There are eight items relating to UI, four of which were designed specifically to quantify the degree of urinary leakage. Twelve items address other symptoms, four associated with the storage phase and eight with the voiding phase. Nine items address additional aspects of QOL and four items address sexual function. The Korean version of the BFLUTS questionnaire has been translated into Korean, and cross-culturally validated linguistically in the Korean language.15 Recently, Brookes et al.16 described the development and validation of a scored form of the BFLUTS questionnaire. Three domains were identified to assess symptoms: UI (5 items, BFLUTS-IS); voiding (3 items, BFLUTS-VS); and filling (4 items, BFLUTS-FS); with additional subscales for sexual function (2 items, BFLUTS-sex) and QOL (5 items, BFLUTS-QoL). All scales have simple additive scores. In this study, we also calculated a scored form of the BFLUTS for the statistical analysis.
The survey responses were coded and analyzed using descriptive statistics, which are reported as the mean and standard error (quantitative variables) or as the number and percentage (qualitative variables). For statistical analysis, patients were divided into patients with SUI and those with OAB. The statistical analysis was carried out using the Student t-test for continuous data and χ2 test or Armitage test for categorical data. A 5% level of significance was used throughout, and all statistical tests were two-sided. The statistical analyses were performed using a commercially available program, SPSS 11.0 (SPSS, Inc., Chicago, IL, USA).
Table 1 shows the baseline patient characteristics of the two groups. The rate of marriage in the SUI group was significantly higher than in the OAB group (87.4% vs 77.2%, P = 0.041). Of free flow parameters, maximum flow rate was higher in the SUI group than in the OAB group (26.1 ± 1.3 mL/s vs 20.9 ± 1.2 mL/s, P = 0.005). Of the daytime parameters on the FV charts, the number of daytime voids was lower in the SUI group (6.8 ± 0.3 vs 8.5 ± 0.4, P < 0.001) and the mean daytime voided volume was significantly higher in the SUI group than in the OAB group (169.6 ± 7.1 vs 143.8 ± 5.8, P = 0.006). Nighttime parameters, however, were not significantly different between the two groups. No differences in other variables were observed in the two groups.
Table 1. Patient characteristics
|Age (years)||50.4 ± 0.8||50.4 ± 1.2||0.972*|
|Symptom duration (months)||62.2 ± 5.5||70.1 ± 7.4||0.395*|
|No. of treatment visits in past year||1.3 ± 0.2||2.5 ± 1.0||0.281*|
|Self-perceived disease severity†|| || ||0.702**|
| Mild||47 (38.8%)||50 (42.4%)|| |
| Moderate||57 (47.1%)||43 (36.4%)|| |
| Severe||17 (14.0%)||25 (21.2%)|| |
|Educational level‡|| || ||0.267**|
| Middle school||53 (44.9%)||47 (41.6%)|| |
| High school||46 (39.0%)||39 (34.5%)|| |
| College||19 (16.1%)||27 (23.9%)|| |
|Monthly income (won)§|| || ||0.056**|
| <1 million||25 (21.2%)||30 (27.3%)|| |
| 1–2 million||31 (26.3%)||38 (34.5%)|| |
| >2 million||62 (52.5%)||42 (38.2%)|| |
|Menopause¶|| || ||0.495***|
| No||70 (58.8%)||62 (54.4%)|| |
| Yes||49 (41.2%)||52 (45.6%)|| |
|Marital status¶|| || ||0.041***|
| Married||104 (87.4%)||88 (77.2%)|| |
| Single, divorced or widowed||15 (12.6%)||26 (22.8%)|| |
| Maximal flow rate (mL/s)||26.1 ± 1.3||20.9 ± 1.2||0.005*|
| Post-void residual (mL)||20.3 ± 3.4||27.5 ± 4.4||0.191*|
| Maximal cystometric capacity (mL)||353.1 ± 10.7||344.7 ± 12.0||0.604*|
| No. uninhibited detrusor contraction (%)||14 (11.4)||16 (13.1)||0.679***|
| No. of daytime voids||6.8 ± 0.3||8.5 ± 0.4||<0.001*|
| Mean daytime voided volume (cc)||169.6 ± 7.1||143.8 ± 5.8||0.006*|
| Actual no. of nightly voids||1.9 ± 0.1||2.0 ± 0.1||0.783*|
| Nocturnal urine volume (cc)||423.0 ± 22.6||440.1 ± 29.4||0.640*|
| Nocturnal bladder capacity index||1.2 ± 0.1||1.1 ± 0.0||0.268*|
| Nocturnal polyuria index||0.3 ± 0.0||0.3 ± 0.0||0.728*|
| Nocturia index||1.4 ± 0.1||1.6 ± 0.1||0.153*|
Of the eight domains in the SF-36 questionnaire, only one domain, namely, ‘general health’ was significantly different between the groups. Patients with SUI had a better general health than those with OAB (P = 0.016). When comparing the BFLUTS scores in the two groups, the score of ‘BFLUTS-FS’ was higher in the OAB group (P = 0.002) but that of ‘BFLUTS-IS’ was higher in the SUI group (P < 0.001). Results are shown in Table 2.
Table 2. Quality of life
|SF-36|| || || |
| Physical functioning||64.2 ± 2.0||69.7 ± 2.3||0.073|
| Role-physical functioning||60.1 ± 3.6||61.3 ± 3.8||0.821|
| Bodily pain||75.9 ± 2.0||74.8 ± 2.4||0.728|
| General health||47.5 ± 1.6||41.9 ± 1.7||0.016|
| Vitality||48.2 ± 2.1||45.0 ± 2.2||0.292|
| Social functioning||72.4 ± 2.1||73.0 ± 2.3||0.864|
| Role-emotional functioning||64.2 ± 3.6||59.7 ± 4.1||0.416|
| Mental health||62.0 ± 1.8||56.9 ± 2.0||0.058|
| Filling symptoms||4.4 ± 0.2||5.6 ± 0.3||0.002|
| Voiding symptoms||2.0 ± 0.2||2.6 ± 0.3||0.056|
| Incontinence symptoms||7.8 ± 0.3||5.6 ± 0.4||<0.001|
| Quality of life||6.0 ± 0.3||5.5 ± 0.4||0.281|
The frequency and associated problem with sexual matters are listed in Table 3. The score of ‘BFLUTS-sex’ was higher in the SUI group than in the OAB group, but this was not statistically significant (P = 0.096). Of 245 patients enrolled in this study, 76 patients (SUI; n = 35, OAB; n = 41) had no sexual activity. Of the 169 patients who had a sex life, the SUI group had experienced pain (P = 0.033) and leakage (P = 0.056) more frequently during intercourse than the OAB group.
Table 3. Sexual function
|BFLUTS-sex||1.0 ± 0.1||0.7 ± 0.1||0.096*|
|Degree of dry vagina|| || ||0.393**|
| Not at all||71 (57.7%)||76 (62.3%)|| |
| A little||39 (31.7%)||38 (31.1%)|| |
| Somewhat||11 (8.9%)||5 (4.1%)|| |
| A lot||2 (1.6%)||3 (2.5%)|| |
|Problem of dry vagina|| || ||0.875**|
| Not at all||77 (62.6%)||78 (63.9%)|| |
| A little||39 (31.7%)||38 (31.1%)|| |
| Somewhat||6 (4.9%)||4 (3.3%)|| |
| A lot||1 (0.8%)||2 (1.6%)|| |
|Degree of sex life spoiled†|| || ||0.309**|
| Not at all||38 (43.2%)||38 (46.9%)|| |
| A little||34 (38.6%)||33 (40.7%)|| |
| Somewhat||11 (12.5%)||8 (9.9%)|| |
| A lot||5 (5.7%)||2 (2.5%)|| |
|Problem of sex life spoiled†|| || ||0.339**|
| Not at all||38 (43.2%)||37 (45.7%)|| |
| A little||32 (36.4%)||32 (39.5%)|| |
| Somewhat||12 (13.6%)||10 (12.3%)|| |
| A lot||6 (6.8%)||2 (2.5%)|| |
|Degree of pain during intercourse†|| || ||0.033**|
| Not at all||49 (55.7%)||55 (67.9%)|| |
| A little||29 (33.0%)||23 (28.4%)|| |
| Somewhat||5 (5.7%)||2 (2.5%)|| |
| A lot||5 (5.7%)||1 (1.2%)|| |
|Problem of pain during intercourse†|| || ||0.032**|
| Not at all||46 (52.3%)||53 (65.4%)|| |
| A little||34 (38.6%)||26 (32.1%)|| |
| Somewhat||4 (4.5%)||1 (1.2%)|| |
| A lot||4 (4.5%)||1 (1.2%)|| |
|Degree of leakage during intercourse†|| || ||0.056**|
| Not at all||50 (56.8%)||56 (69.1%)|| |
| A little||29 (33.0%)||22 (27.1%)|| |
| Somewhat||4 (4.5%)||1 (1.2%)|| |
| A lot||5 (5.7%)||2 (2.5%)|| |
|Problem of leakage during intercourse†|| || ||0.026**|
| Not at all||48 (54.5%)||56 (69.1%)|| |
| A little||29 (33.0%)||21 (25.9%)|| |
| Somewhat||7 (8.0%)||3 (3.7%)|| |
| A lot||4 (4.5%)||1 (1.2%)|| |
Patient-completed FV charts are commonly used in clinical trials as a primary tool for measuring subjective symptoms of the lower urinary tract. The FV charts allow the clinician to obtain information about voiding frequency, nocturia, the mean volume of urine passed, and provide documentation on voiding patterns to be established in the patient's environment and during various daily activities. To date, there are few prospective studies comparing the micturition patterns in women with SUI and OAB. As expected, in this study, patients with OAB had more daytime voids than those with SUI on the FV charts, although the actual number of nightly voids was not statistically significant. These findings support that the scores on ‘BFLUTS-FS’ of the BFLUTS were higher in the OAB group than in the SUI group.
The SF-36 is a generic measure of health status as opposed to one that targets a specific age, disease, or treatment group. Accordingly, the SF-36 has proven useful in comparing general and specific populations, estimating the relative burden of different diseases, differentiating the health benefits produced by a wide range of different treatments, and screening individual patients.17 Although generic HRQOL instruments can be used for assessment, however they may lack sensitivity to the characteristics of SUI or OAB and its impact. In the present study, we found that only the ‘general health’ domain was significantly different between the groups. Similarly, Ho-Yin et al.18 showed that the SF-36 was unable to detect a significant difference in HRQOL measurements between women suffering from genuine SUI and detrusor instability.
Patients with UUI cannot predict incontinence episodes, and thus have less control over their bladder symptoms, whereas those with SUI can adapt their lifestyle by, e.g. avoiding heavy lifting or exercising and thus prevent situations that lead to involuntary loss of urine. Since the pathophysiology and symptomatic presentation of SUI and OAB differ, this may affect HRQOL differently. In the present study, however, when comparing the BFLUTS scores between the SUI and OAB groups, the scores for ‘BFLUTS-FS’ were higher in the OAB group, while the scores for ‘BFLUTS-IS’ were higher in the SUI group. The scores for ‘BFLUTS-VS’ and ‘BFLUTS-QoL’ were not significantly different between the two groups. Most studies have indicated a greater impact on HRQOL for the urge component than for the stress component. It is difficult to interpret, but some possible explanations for our results exist. Although in general, OAB has a greater impact than SUI on HRQOL, some studies suggest that the impact of urinary incontinence is not solely a function of its severity, but also depends on individual coping abilities.19 In addition, the impact of urinary incontinence may vary owing to other factors such as age and cultural belief.20 Therefore, because HRQOL can be influenced by the patient's sociocultural background, additional studies in various populations are warranted. Furthermore, subjective HRQOL results of urinary incontinence using the specific-condition HRQOL questionnaire can be different because there are a plethora of measurement instruments that vary in scope and content, depending on their intended purpose and target population.
Although biased towards assessing urinary incontinence, the BFLUTS instrument was intended to cover all symptoms pertaining to female lower urinary tract dysfunction. Thus, unlike most other questionnaires, the BFLUTS includes not only the range of symptoms of urinary incontinence but also a number of other troublesome lower urinary tract symptoms that are not commonly included in other questionnaires. In our cohort, patient age and the rate of menopause were similar between the two groups, however one of the most interesting findings is that women with SUI have more frequently experienced pain and leakage during intercourse than those with OAB. Recently, Kizilkaya Beji et al.8 demonstrated that urinary leakage during coitus affected women's sexual life adversely. Although Moran et al.21 suggested that the underlying mechanism of coital incontinence was urethral sphincter incompetence, the major mechanisms that cause coital incontinence are not known. Additional research is needed to clarify the underlying mechanisms involved.
Some limitations should be pointed out with regard to the study design. First, this study was not a prevalence study because we recruited study subjects from the clinic, making it difficult to generalize the study results. Second, our study included only Korean women, so our results may not be applicable to other races and cultures. Although the potential influences of sociocultural settings on the concept of HRQOL have only recently been appreciated, the interpretation of findings in HRQOL studies must be guided by an awareness of the cultural composition of the study population, which may vary between countries.22 We believe that it would be useful to perform this type of study in distinct patient populations, because cultural differences might alter the results. Finally, one of the difficulties investigating sexual function was the variation in measures and definitions between studies. Further research is needed using standard definitions and measures of sexual function in order to target screening and treatment interventions more effectively.
Both SUI and OAB have a detrimental impact on patient HRQOL in Korean women. In addition, our findings suggest that women with SUI had more frequently experienced pain during intercourse and coital incontinence than those with OAB.